A gear switch of this type is known from DT-PS 25 02 578. This gear switch comprises a shift lever mobile in two parallel links. The two links finish in a switch track perpendicular to the links, in which the shift lever can be moved, by slightly lifting and then lowering it into the position for forward or reverse travel. When this gear switch is fixed to the steering column, it is not clear to the eye of the driver whether the shift lever has assumed the forward or reverse travel position. When the number of gears is large, the shift lever has a large angle of swing. The shift lever and drum controller for controlling the gears are connected together by means of an elastic hinge. This prejudices the accuracy of the instant of switching both for the gear change and for the change in the direction of travel.
German laid-open specification No. 18 04 125 describes a manoeuvring device for a change-over and reversing gear for construction vehicles, which comprises a gear shift lever which is rotatable about its longitudinal axis and can be swivelled about an axis perpendicular to this latter. It is supported in a ball-and-socket joint, and is connected, by way of the end distant from the handgrip, to a mechanical linkage for switching-in the reversing gear. The known gear switch requires high shifting forces, and is not suitable as a steering wheel switch for construction vehicles with their frequent changes in the direction of travel. The robust support for the shift lever, required because of the high shifting forces, is also unsuitable for the use of microswitches.
The object was therefore to provide an easily operable gear switch, in which the contact travel distance involved in controlling the gears is small, in which when the gear switch is viewed in plan the positions for forward and reverse travel are clearly recognisable, and which allows the switching instants to be made precise.
This object was attained by the invention described in patent application DE-OS No. 29 34 473.